Known working vehicles, such as back hoe loaders have a materials handling implement such as a loading shovel mounted on the front of the machine and a further materials handling implement such as a back hoe, mounted on the back of a machine.
When the operator wishes to use the loading shovel the seat is orientated in a forwards facing direction and the operator can use controls such as the steering wheel, a foot brake, a foot clutch, a foot accelerator, a gear box having forward and reverse gears to move the vehicle over the ground. Hand operated controls can also be used to lift and lower a loading arm and crowd or dump the loading shovel. Accordingly material can be manoeuvred.
When it is necessary to move the back hoe loader from one location to another location, typically via public highway, the loading shovel will be lifted above ground level and the back hoe loader can be driven, in the manner of a car (automobile) with the operator facing forwards and using the steering wheel, brake, clutch and throttle controls.
When using the back hoe the seat can be rotated to face rearwardly. When using the back hoe the vehicle will be stationary, and indeed some or all of the wheels may be lifted off the ground by operation of stabilizer legs and/or lowering of the front shovel into engagement with the ground. Known back hoe loaders have a stabilizer on the rear right hand side of the machine and a further stabilizer on the rear left hand side of the machine. Each stabilizer is controlled individually by a separate operator input, i.e. there is one operator input which only controls the right hand stabilizer and a further operator input which only controls the left hand stabilizer. Prior to using the back hoe each stabilizer is engaged with the ground. Typically it is desirable for the rear right and rear left stabilizers to lift the chassis of the vehicle slightly such that the weight of the vehicle is taken on the stabilizers and removed from the wheels, in particular the pneumatic tires of the wheels. Taking weight of the vehicle on the stabilizers and removing it from the tires means that during operation the vehicle will not rock on the pneumatic tires. Furthermore, because each stabilizer is individually controllable, then it is possible to orientate the vehicle at a desired roll angle. Setting the vehicle at a desired roll angle is important since it orientates the generally vertical pivot about which the back hoe swings. Typically the operator will engage both stabilizers with the ground and then adjust both until the desired roll angle has been achieved and sufficient weight of the vehicle has been taken by the stabilizers.
Clearly, the final adjustments of the individual stabilizers is time consuming and delays use of the back hoe.